2 5 Ja n 20 16 Measurement of the φ → π 0 e + e − transition form factor with the KLOE detector

نویسندگان

  • P. Branchini
  • F. Ceradini
  • A. De Santis
  • A. Di Cicco
  • A. Di Domenico
  • R. Di Salvo
  • D. Domenici
  • A. Fantini
  • P. Gauzzi
  • G. Giardina
  • E. Graziani
  • P. Moskal
  • A. Passeri
  • P. Santangelo
چکیده

A measurement of the vector to pseudoscalar conversion decay φ → πee with the KLOE experiment is presented. A sample of ∼ 9500 signal events was selected from a data set of 1.7 fb of ee collisions at √ s ∼ mφ collected at the DAΦNE ee collider. These events were used to obtain the first measurement of the transition form factor |Fφπ0(q)| and a new measurement of the branching ratio of the decay: BR (φ → πee) = ( 1.35 ± 0.05 +0.05 −0.10 ) × 10. The result improves significantly on previous measurements and is in agreement with theoretical predictions.

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تاریخ انتشار 2016